U.S. patent number 10,575,400 [Application Number 15/795,774] was granted by the patent office on 2020-02-25 for light-emitting module.
This patent grant is currently assigned to Toshiba Hokuto Electronics Corporation. The grantee listed for this patent is TOSHIBA HOKUTO ELECTRONICS CORPORATION. Invention is credited to Keiichi Maki.
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United States Patent |
10,575,400 |
Maki |
February 25, 2020 |
Light-emitting module
Abstract
A light-emitting module according to an embodiment includes a
first insulating film with light transmissive property, a plurality
of mesh patterns including a plurality of first line patterns and a
plurality of second line patterns, a light-emitting element, and a
resin layer. The first line patterns are formed on the first
insulating film and are parallel to one another. The second line
patterns intersect with the first line patterns and are parallel to
one another. The light-emitting element is connected to any two of
a plurality of the mesh patterns. The resin layer holds the
light-emitting element to the first insulating film. A first mesh
pattern and a second mesh pattern adjacent to one another among the
plurality of mesh patterns have a boundary. Line patterns
projecting from the first mesh pattern to the boundary and line
patterns projecting from the second mesh pattern to the boundary
are collocated along the boundary in a state of being adjacent to
one another.
Inventors: |
Maki; Keiichi (Suita,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
TOSHIBA HOKUTO ELECTRONICS CORPORATION |
Asahikawa-shi |
N/A |
JP |
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Assignee: |
Toshiba Hokuto Electronics
Corporation (Asahikawa-Shi, JP)
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Family
ID: |
57218252 |
Appl.
No.: |
15/795,774 |
Filed: |
October 27, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20180049318 A1 |
Feb 15, 2018 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/JP2016/002237 |
Apr 28, 2016 |
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Foreign Application Priority Data
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May 1, 2015 [JP] |
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2015-094066 |
May 29, 2015 [JP] |
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2015-109959 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F21V
23/005 (20130101); F21V 23/00 (20130101); F21V
19/0025 (20130101); H05K 1/111 (20130101); F21S
2/00 (20130101); H01L 33/62 (20130101); F21V
19/002 (20130101); H05K 1/0298 (20130101); H05K
1/0274 (20130101); H05K 1/189 (20130101); F21V
19/00 (20130101); H05K 1/181 (20130101); H05K
3/284 (20130101); H05K 2201/0145 (20130101); H01L
2924/181 (20130101); H05K 2201/0129 (20130101); H05K
2201/09227 (20130101); H05K 2201/09245 (20130101); H01L
2224/16225 (20130101); H05K 2201/10106 (20130101); F21Y
2115/10 (20160801); H05K 2201/09681 (20130101); H05K
2201/0108 (20130101); H05K 2201/0133 (20130101); H01L
2924/181 (20130101); H01L 2924/00012 (20130101) |
Current International
Class: |
H05K
1/02 (20060101); F21V 23/00 (20150101); F21V
19/00 (20060101); H05K 1/11 (20060101); H05K
1/18 (20060101) |
Field of
Search: |
;174/260 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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S63-084966 |
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Jun 1988 |
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JP |
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2011-134926 |
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Jul 2011 |
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JP |
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2012-084855 |
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Apr 2012 |
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JP |
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2015-073103 |
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Apr 2015 |
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JP |
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2014/157455 |
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Oct 2014 |
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WO |
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Other References
International Search Report and Written Opinion (Application No.
PCT/JP2016/002237) dated Aug. 2, 2016. cited by applicant.
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Primary Examiner: Tso; Stanley
Attorney, Agent or Firm: Burr & Brown, PLLC
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is continuation of International Application No.
PCT/JP2016/002237, filed on Apr. 28, 2016, which is based upon and
claims the benefit of priority from the prior Japanese Patent
Applications No. 2015-094066 filed on May 1, 2015 and No.
2015-109959 filed on May 29, 2015. The entire specifications,
claims, and drawings of Japanese Patent Applications No.
2015-094066 and No. 2015-109959 are herein incorporated in this
specification by reference.
Claims
The invention claimed is:
1. A light-emitting module comprising: a first insulating film, the
first insulating film at least partially light transmissive; a
plurality of conductor patterns comprising at least a first
conductor pattern and a second conductor pattern; at least a first
light-emitting element, an anode of the first light-emitting
element connected to the first conductor pattern and a cathode of
the first light-emitting element connected to the second conductor
pattern; and a resin layer that holds the light-emitting element to
the first insulating film, the first conductor pattern comprising a
plurality of first conductor pattern conductive lines on the first
insulating film, the second conductor pattern comprising a
plurality of second conductor pattern conductive lines on the first
insulating film, a gap between the first conductor pattern and the
second conductor pattern, the first conductor pattern and the
second conductor pattern adjacent to each other along the gap, in
at least a first portion of the gap; some of the first conductor
pattern conductive lines project into the gap and extend more than
halfway across the gap, and some of the second conductor pattern
conductive lines project into the gap and extend more than halfway
across the gap.
2. The light-emitting module according to claim 1, wherein: the
first conductor pattern conductive lines comprise: a plurality of
first conductive lines, the first conductive lines being parallel
to one another; and a plurality of second conductive lines
intersecting with the first conductive lines, the second conductive
lines being parallel to one another.
3. The light-emitting module according to claim 2, wherein: the
first conductor pattern conductive lines project into the gap from
a first boundary of the gap, the second conductor pattern
conductive lines project into the gap from a second boundary of the
gap, and the first conductor pattern conductive lines that project
into the gap from the first boundary of the gap and the second
conductor pattern conductive lines that project into the gap from
the second boundary of the gap are arranged in alternation along
the gap.
4. The light-emitting module according to claim 2, wherein: the
first conductor pattern comprises a first pad to which the anode of
the first light-emitting element is connected, two or more of the
first conductor pattern conductive lines are connected to the first
pad, the second conductor pattern comprises a second pad to which
the cathode of the first light-emitting element is connected, and
two or more of the second conductor pattern conductive lines are
connected to the second pad.
5. The light-emitting module according to claim 2, wherein the
light-emitting module further comprises a second insulating film
disposed opposed to the first insulating film.
6. The light-emitting module according to claim 5, wherein: the
light-emitting module further comprises a mesh pattern formed on
the second insulating film, the mesh pattern being constituted of a
plurality of mesh pattern conductive lines, wherein the first
conductive lines and the second conductive lines intersect with the
mesh pattern conductive lines.
7. The light-emitting module according to claim 6, wherein the mesh
pattern conductive lines include curved lines.
8. The light-emitting module according to claim 6, wherein at least
one of the first conductor pattern conductive lines and the second
conductor pattern conductive lines are curved lines.
9. The light-emitting module according to claim 1, wherein: the
light-emitting module comprises a plurality of light-emitting
elements connected to a control circuit, the control circuit being
configured to control the light-emitting elements that are
connected to the control circuit, and the light-emitting elements
that are connected to the control circuit are in parallel to one
another.
10. The light-emitting module according to claim 9, wherein ones of
the anodes and the cathodes of the respective light-emitting
elements are connected to a common conductor pattern.
11. The light-emitting module according to claim 1, wherein: the
light-emitting module comprises a plurality of light-emitting
elements disposed on a predetermined curved line, and the conductor
patterns have a fan shape specified by one set of straight lines
perpendicular to the curved line.
12. The light-emitting module according to claim 1, wherein: the
light-emitting module comprises a plurality of light-emitting
elements disposed on a predetermined curved line, and the
respective conductor patterns are adjacent to one another via a
side parallel to a predetermined straight line intersecting with
the curved line.
13. The light-emitting module according to claim 1, wherein: the
light-emitting module comprises a plurality of light-emitting
elements, the first conductor pattern conductive lines comprise: a
plurality of first conductive lines, the first conductive lines
being parallel to one another; a plurality of second conductive
lines intersecting with the first conductive lines, the second
conductive lines being parallel to one another; and first
connecting pads to which the light-emitting elements are connected,
and the first connecting pads are connected to respective first
conductive lines and respective second conductive lines.
14. The light-emitting module according to claim 1, wherein: the
first conductor pattern conductive lines comprise curved lines or
polygonal shapes.
15. The light-emitting module according to claim 1, wherein the
first conductor pattern conductive lines comprise: a plurality of
first conductive lines, the first conductive lines being parallel
to one another; and a plurality of second conductive lines
intersecting with the first conductive lines, the second conductive
lines being parallel to one another, and one of the plurality of
conductor patterns and a wiring layer with a different height form
a multilayer wiring.
16. The light-emitting module according to claim 1, wherein each of
the conductor patterns comprises: a plurality of first conductive
lines, the first conductive lines being parallel to one another;
and a plurality of second conductive lines intersecting with the
first conductive lines, the second conductive lines being parallel
to one another, and the plurality of conductor patterns or a unit
of the plurality of conductor patterns and the first insulating
film has a transmittance of 75% or more, and the conductor patterns
has a sheet resistance of 100.OMEGA. or less.
17. The light-emitting module according to claim 16, wherein the
plurality of conductor patterns have the sheet resistance of
70.OMEGA. or less.
18. The light-emitting module according to claim 16, wherein the
plurality of conductor patterns have the sheet resistance of
30.OMEGA. or less.
19. The light-emitting module according to claim 16, wherein each
of the first conductive lines and the second conductive lines has a
line width of 20 .mu.m or less.
20. The light-emitting module according to claim 16, wherein the
first conductive lines have an arrangement pitch of 500 .mu.m or
less, and the second conducive lines have an arrangement pitch of
500 .mu.m or less.
21. The light-emitting module according to claim 1, wherein the
plurality of conductor patterns are constituted of fan shapes or
sides parallel to a predetermined straight line, the plurality of
conductor patterns having a surface formed into a curved
surface.
22. The light-emitting module according to claim 1, wherein: the
first pattern conductive lines project into the gap from a first
boundary of the gap, the second pattern conductive lines project
into the gap from a second boundary of the gap, and the gap between
the first conductor pattern conductive lines that project from the
first boundary of the gap and the second conductor pattern
conductive lines that project from the second boundary of the gap
is a wave shape.
23. The light-emitting module according to claim 1, wherein: the
first pattern conductive lines project into the gap from a first
boundary of the gap, the second pattern conductive lines project
into the gap from a second boundary of the gap, and the gap between
the first conductor pattern conductive lines that project from the
first boundary of the gap and the second conductor pattern
conductive lines that project from the second boundary of the gap
is a zigzag shape.
24. The light-emitting module according to claim 1, wherein a
straight line cannot pass between the first conductor pattern
conductive lines that project at the first boundary and the second
conductor pattern conductive lines that project at the second
boundary, and a wave shape can pass between the first conductor
pattern conductive lines that project at the first boundary and the
second conductor pattern conductive lines that project at the
second boundary.
Description
FIELD
Embodiments of the present disclosure relate to a light-emitting
module.
BACKGROUND
Recently, efforts aiming to a reduction in energy consumption have
been regarded as important. From such background, a Light-emitting
Diode (LED) whose power consumption is comparatively small attracts
attention as a next-generation light source. The LED features
downsizing, small amount of heat generation, and good
responsiveness. In view of this, the LED has been widely used as a
display device, for example, for indoor, for outdoor, for
stationary, and for movement; and an optical device such as an
indicator lamp, various kinds of switches, a signal device, and a
general illumination.
A wire bonding method has been conventionally used to mount this
kind of LED to a wiring board. However, the wire bonding method is
not suitable for mounting a LED chip to a flexible material such as
a flexible substrate. Therefore, techniques for mounting the LED
chip without the use of the wire bonding method have been variously
proposed.
In a conventional module, the LED chip is disposed between one set
of light transmissive films where light transmissive electrodes are
formed. This kind of module is required to efficiently supply
electric power to the LED chip while securing light transmissive
property and flexibility of the module.
This kind of module is required to include a conductor pattern on
the light transmissive substrate without sacrificing light
transmissive property. However, when the plurality of conductor
patterns are disposed on the substrate, a light transmittance at
regions between the conductor patterns differs from a light
transmittance at regions where the conductor patterns are formed.
In view of this, depending on a shape and a positional relationship
of the conductor patterns, the light transmittance possibly varies
in the entire module. Especially, in the case where the plurality
of conductor patterns are gaplessly disposed on the substrate,
lines along outer edges of the conductor patterns stand out, also
losing limpidity in appearance.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a light-emitting module according
to a first embodiment.
FIG. 2 is a developed perspective view of the light-emitting
module.
FIG. 3 is a side view of a light-emitting panel.
FIG. 4 is a plan view of the light-emitting module.
FIG. 5 is a perspective view of a light-emitting element.
FIG. 6 is a drawing illustrating the light-emitting element
connected to a mesh pattern.
FIG. 7 is a drawing illustrating enlarged mesh patterns.
FIG. 8 is a side view of a flexible cable.
FIG. 9 is a drawing describing a point of connecting of the
light-emitting panel to the flexible cable.
FIG. 10 is a drawing describing a point of manufacturing the mesh
patterns.
FIG. 11 is a drawing describing the point of manufacturing the mesh
patterns.
FIG. 12 is a drawing describing the point of manufacturing the mesh
patterns.
FIG. 13 is a drawing describing a point of manufacturing the mesh
patterns.
FIG. 14 is a drawing describing a point of manufacturing the mesh
patterns.
FIG. 15 is a drawing describing a point of manufacturing the
light-emitting panel.
FIG. 16 is a drawing describing a point of manufacturing the
light-emitting panel.
FIG. 17 is a drawing illustrating a modification of the mesh
patterns.
FIG. 18A is a (first) drawing illustrating a correspondence table
expressing transmittances corresponding to line widths and pitches
of thin film conductors constituting the mesh pattern.
FIG. 18B is a (second) drawing illustrating a correspondence table
expressing transmittances corresponding to line widths and pitches
of thin film conductors constituting the mesh pattern.
FIG. 18C is a (third) drawing illustrating a correspondence table
expressing transmittances corresponding to line widths and pitches
of thin film conductors constituting the mesh pattern.
FIG. 19 is a plan view of a light-emitting module according to a
second embodiment.
FIG. 20 is a plan view of a light-emitting module according to a
modification.
FIG. 21 is a plan view of a light-emitting module according to a
modification.
FIG. 22A is a drawing illustrating the enlarged mesh patterns of a
light-emitting module according to a third embodiment.
FIG. 22B is a drawing illustrating a modification of the mesh
pattern.
FIG. 22C is a drawing illustrating a modification of the mesh
pattern.
FIG. 22D is a drawing illustrating a modification of the mesh
pattern.
FIG. 23A is a drawing illustrating a wiring example of a
light-emitting module according to a fourth embodiment.
FIG. 23B is a drawing illustrating a wiring example of the
light-emitting module.
FIG. 23C is a drawing illustrating a wiring example of the
light-emitting module.
FIG. 24A is a drawing illustrating a wiring example of the
light-emitting module.
FIG. 24B is a drawing illustrating a wiring example of the
light-emitting module.
FIG. 25A is a plan view illustrating an example of a mesh pattern
of a light-emitting module according to a fifth embodiment.
FIG. 25B is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 25C is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 25D is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 25E is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 25F is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 26 is a plan view of mesh patterns according to a six
embodiment.
FIG. 27 is a plan view of mesh patterns.
FIG. 28 is a perspective view of a light-emitting element.
FIG. 29 is a side view of a light-emitting panel.
FIG. 30A is a plan view illustrating a mesh pattern of a
light-emitting module.
FIG. 30B is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 30C is a plan view illustrating a mesh pattern of the
light-emitting module.
FIG. 31A is a plan view illustrating line patterns.
FIG. 31B is a plan view illustrating line patterns.
FIG. 31C is a plan view illustrating line patterns.
FIG. 31D is a plan view illustrating line patterns.
DETAILED DESCRIPTION
A light-emitting module according to an embodiment, for example, a
first mesh pattern and a second mesh pattern adjacent to one
another among a plurality of mesh patterns have a boundary. Line
patterns of the first mesh pattern and line patterns of the second
mesh pattern are collocated along the boundary in a state of being
adjacent to one another.
First Embodiment
The following describes the first embodiment of the present
disclosure with reference to the drawings. An XYZ coordinate system
constituted of an X-axis, a Y-axis, and a Z-axis perpendicular to
one another is used for explanation.
FIG. 1 is a perspective view of a light-emitting module 10
according to the embodiment. FIG. 2 is a developed perspective view
of the light-emitting module 10. As apparent with reference to FIG.
1 and FIG. 2, the light-emitting module 10 includes a
light-emitting panel 20, a flexible cable 40, a connector 50, and a
reinforcing plate 60.
FIG. 3 is a side view of the light-emitting panel 20. As
illustrated in FIG. 3, the light-emitting panel 20 includes one set
of light transmissive films 21 and 22, a resin layer 24, which is
formed between the light transmissive films 21 and 22, and eight
pieces of light-emitting elements 30.sub.1 to 30.sub.8, which are
disposed inside the resin layer 24.
The light transmissive films 21 and 22 are rectangular films having
the longitudinal direction in the X-axis direction. The light
transmissive film 21 has the thickness of around 50 to 300 .mu.m
and has light transmissive property to visible light. A total light
transmittance of the light transmissive film 21 is preferably
around 5 to 95%. The total light transmittance means total light
transmittance measured compliant with the Japanese Industrial
Standards JISK7375:2008.
The light transmissive films 21 and 22 have flexibility and the
flexural modulus is around 0 to 320 kgf/mm.sup.2 (excluding zero).
The flexural modulus is a value measured by a method compliant with
ISO178 (JIS K7171:2008).
As the material of the light transmissive films 21 and 22, for
example, a polyethylene terephthalate (PET), a polyethylene
naphthalate (PEN), a polycarbonate (PC), a polyethylene succinate
(PES), an arton (ARTON), and an acrylic resin are considered for
use.
Among one set of the light transmissive films 21 and 22, a
conductor layer 23 with a thickness of around 0.05 .mu.m to 2 .mu.m
is formed on a lower surface (-Z-side surface in FIG. 3) of the
light transmissive film 21.
FIG. 4 is a plan view of the light-emitting module 10. As apparent
with reference to FIG. 3 and FIG. 4, the conductor layer 23 is
constituted of an L-shaped mesh pattern 23a, which is formed along
the +Y-side outer edge of the light transmissive film 21, and
rectangular mesh patterns 23b to 23i, which are collocated along
the -Y-side outer edge of the light transmissive film 21. The mesh
patterns 23a to 23i are made of a metallic material such as a
copper (Cu) and an argentum (Ag). In the light-emitting module 10,
a distance D between the mesh patterns 23a to 23i is about 100
.mu.m or less.
As apparent with reference to FIG. 3, in the light-emitting module
10, the light transmissive film 22 has a length in the X-axis
direction shorter than that of the light transmissive film 21. In
view of this, the +X-side ends of the mesh pattern 23a and the mesh
pattern 23i constituting the conductor layer 23 are exposed.
The resin layer 24 is formed between the light transmissive films
21 and 22. The resin layer 24 has light transmissive property to
the visible light.
The resin layer 24 has a Vicat softening temperature in a range of
80.degree. C. or more to 160.degree. C. or less and a tensile
storage elastic modulus from 0.degree. C. to 100.degree. C. in a
range of 0.01 GPa or more to 10 GPa or less. The tensile storage
elastic modulus of the resin layer 24 at the Vicat softening
temperature is 0.1 MPa or more. A melting temperature of the resin
layer 24 is 180.degree. C. or more or preferably higher than the
Vicat softening temperature by 40.degree. C. or more. A
glass-transition temperature of the resin layer 24 is preferably
-20.degree. C. or less. The resin layer 24 is a thermoplastic
resin, for example, a thermoplastic elastomer. As the elastomer
used for the resin layer 24, for example, an acrylic-based
elastomer, an olefin-based elastomer, a styrene-based elastomer, an
ester-based elastomer, and an urethane-based elastomer are
considered.
The light-emitting element 30.sub.1 is a square LED chip with one
side of 0.3 mm to 3 mm. As illustrated in FIG. 5, the
light-emitting element 30.sub.1 is an LED chip with a four-layer
structure constituted of a base substrate 31, an N-type
semiconductor layer 32, an active layer 33, and a P-type
semiconductor layer 34. The light-emitting element 30.sub.1 has a
rated voltage of about 2.5 V.
The base substrate 31 is a sapphire substrate or a semiconductor
substrate. The N-type semiconductor layer 32 with a shape identical
to this base substrate 31 is formed on the top surface of the base
substrate 31. The active layer 33 and the P-type semiconductor
layer 34 are laminated in order on the top surface of the N-type
semiconductor layer 32. A cutout is formed at a corner part on the
-Y-side and the -X-side of the active layer 33 and the P-type
semiconductor layer 34 laminated on the N-type semiconductor layer
32. The surface of the N-type semiconductor layer 32 is exposed
from this cutout. The use of one having light transmissive property
as the base substrate 31 radiates light from both upper and lower
surfaces of the light-emitting element.
A pad 36 is formed at the part of the N-type semiconductor layer 32
exposed from the active layer 33 and the P-type semiconductor layer
34 for electrical connection to the N-type semiconductor layer 32.
A pad 35 is formed at a corner part on the +X-side and the +Y-side
of the P-type semiconductor layer 34 for electrical connection to
the P-type semiconductor layer 34. The pads 35 and 36 are made of a
copper (Cu) or a gold (Au) and includes bumps 37 and 38 on the top
surfaces. The bumps 37 and 38 are made of a metal such as a gold
(Au) and a gold alloy. As the bumps 37 and 38, instead of the metal
bump, a solder bump shaped to a hemispherical shape may be used. In
a light-emitting element 30, the bump 37 functions as a cathode
electrode and the bump 38 functions as an anode electrode.
As illustrated in FIG. 6, the light-emitting element 30.sub.1
constituted as described above is disposed between the mesh
patterns 23a and 23b. While the bump 37 is connected to the mesh
pattern 23a, the bump 38 is connected to the mesh pattern 23b.
FIG. 7 is drawing illustrating the enlarged mesh patterns 23a and
23b. As apparent with reference to FIG. 7, the mesh patterns 23a
and 23b are constituted of a plurality of line patterns LX parallel
to the X-axis and a plurality of line patterns LY parallel to the
Y-axis. The mesh patterns 23a to 23i each include a connecting pad
P to which the bumps 37 and 38 of the light-emitting element 30 are
connected.
The respective line widths of the line patterns LX and LY are about
10 .mu.m and are formed at pitches of about 300 .mu.m. As indicated
by the arrow in FIG. 7, end portions of the line patterns LX
constituting the mesh pattern 23a project every other line pattern
LX at the boundary parallel to the Y-axis among boundaries of the
mesh patterns 23a and 23b. Similarly, end portions of the line
patterns LX constituting the mesh pattern 23b project every other
line pattern LX at the boundary of the mesh patterns 23a and 23b
parallel to the Y-axis. In view of this, at the boundary of the
mesh patterns 23a and 23b, the line patterns LX of the mesh pattern
23a and the line patterns LX of the mesh pattern 23b are arranged
in alternation along this boundary.
End portions of the line patterns LY constituting the mesh pattern
23a project every other line pattern LY at the boundary parallel to
the X-axis among boundaries of the mesh patterns 23a and 23b.
Similarly, end portions of the line patterns LY constituting the
mesh pattern 23b project every other line pattern LY at the
boundary of the mesh patterns 23a and 23b parallel to the X-axis.
In view of this, at the boundary of the mesh patterns 23a and 23b,
the line patterns LY of the mesh pattern 23a and the line patterns
LY of the mesh pattern 23b are arranged in alternation along this
boundary.
As illustrated in FIG. 7, the light-emitting element 30.sub.1 is
disposed across the mesh patterns 23a and 23b so as to traverse the
boundary. The bump 37 is connected to the connecting pad P disposed
at the mesh pattern 23a, and the bump 38 is connected to the
connecting pad P disposed at the mesh pattern 23b.
The mesh patterns 23c to 23i are also formed similarly to the mesh
patterns 23a and 23b illustrated in FIG. 7. Other light-emitting
elements 30.sub.2 to 30.sub.8 also have a configuration similar to
the light-emitting element 30.sub.1.
The light-emitting element 30.sub.2 is disposed between the mesh
patterns 23b and 23c, and the bumps 37 and 38 are connected to the
respective mesh patterns 23b and 23c. Hereinafter, similarly, the
light-emitting element 30.sub.3 is disposed across the mesh
patterns 23c and 23d. The light-emitting element 30.sub.4 is
disposed across the mesh patterns 23d and 23e. The light-emitting
element 30.sub.5 is disposed across the mesh patterns 23e and 23f.
The light-emitting element 30.sub.6 is disposed across the mesh
patterns 23f and 23g. The light-emitting element 30.sub.7 is
disposed across the mesh patterns 23g and 23h. The light-emitting
element 30.sub.8 is disposed across the mesh patterns 23h and 23i.
Thus, the mesh patterns 23a to 23i and the light-emitting elements
30.sub.1 to 30.sub.8 are connected in series. In the light-emitting
panel 20, the light-emitting elements 30 are disposed at intervals
of 10 mm.
FIG. 8 is a side view of the flexible cable 40. As illustrated in
FIG. 8, the flexible cable 40 is constituted of a base material 41,
a conductor layer 43, and a coverlay 42.
The base material 41 is a rectangular member having the
longitudinal direction in the X-axis direction. This base material
41 is, for example, made of a polyimide and includes the conductor
layer 43 on the top surface. The conductor layer 43 is formed by
patterning a copper foil pasted to the top surface of the
polyimide. As illustrated in FIG. 4, the conductor layer 43 of this
embodiment is constituted of two conductor patterns 43a and
43b.
As illustrated in FIG. 8, the conductor layer 43, which is formed
on the top surface of the base material 41, is coated by the
coverlay 42 on which vacuum thermocompression bonding is performed.
This coverlay 42 has a length shorter than the base material 41 in
the X-axis direction. In view of this, end portions on the -X-side
of the conductor patterns 43a and 43b constituting the conductor
layer 43 are exposed. The coverlay 42 has an opening 42a from which
the end portions on the +X-side of the conductor patterns 43a and
43b are exposed.
As apparent with reference to FIG. 4 and FIG. 9, the flexible cable
40 configured as described above is bonded to the light-emitting
panel 20 while the conductor patterns 43a and 43b exposed from the
coverlay 42 are in contact with the end portions on the +X-side of
the mesh patterns 23a and 23i of the light-emitting panel 20.
As illustrated in FIG. 2, the connector 50 is a rectangular
parallelepiped-shaped component. A cable extended from a DC power
supply is connected to the connector 50. The connector 50 is
implemented on the end portion on the +X-side of the top surface of
the flexible cable 40. As illustrated in FIG. 9, when the connector
50 is implemented on the flexible cable 40, a pair of respective
terminals 50a of the connector 50 are connected to the conductor
patterns 43a and 43b constituting the conductor layer 43 via the
opening 42a disposed at the coverlay 42.
As illustrated in FIG. 2, the reinforcing plate 60 is a rectangular
plate-shaped member having the longitudinal direction in the X-axis
direction. The reinforcing plate 60 is, for example, made of an
epoxy resin and an acrylic. As illustrated in FIG. 9, this
reinforcing plate 60 is pasted to the lower surface of the flexible
cable 40. In view of this, the flexible cable 40 can be bent
between the -X-side end of the reinforcing plate 60 and the +X-side
end of the light-emitting panel 20.
The following describes a method for manufacturing the
light-emitting panel 20 constituting the above-described
light-emitting module 10. First, the light transmissive film 21
made of PET is prepared. As illustrated in FIG. 10, the mesh-like
conductor layer 23 is formed on the entire surface of the light
transmissive film 21 using, for example, a subtract method or an
additive method. Cutting this conductor layer 23 using laser forms
the mesh patterns 23a to 23i.
The conductor layer 23 is cut by irradiating laser light to the
conductor layer 23, which is formed on the surface of the light
transmissive film 21. A laser spot of the laser light is moved
along the dotted line illustrated in FIG. 11. Thus, the conductor
layer 23 is cut along the dotted line and as illustrated in FIG.
12, the mesh patterns 23a to 23i are formed.
FIG. 13 is a drawing illustrating the enlarged conductor layer 23.
As illustrated in FIG. 12, to move the laser spot and cut the
conductor layer 23, as illustrated by the dotted line in the
drawing, the laser spot is moved zigzag with amplitude smaller than
the arrangement pitches of the line patterns LX and LY.
Accordingly, at the boundary of the adjacent mesh patterns, the end
portions of one mesh pattern and the end portions of the other mesh
pattern are arranged in alternation along the boundary.
As illustrated in FIG. 13, this embodiment preliminarily forms the
connecting pad P at the conductor layer 23. The connecting pad P is
disposed corresponding to the position on which the light-emitting
element 30 is implemented when the conductor layer 23 is formed.
When the laser spot of the laser light moves on the surface of the
conductor layer 23 along the dotted line illustrated in FIG. 13, a
part of the line patterns LX and LY near the movement path of the
laser spot melt and sublime. This cuts out the mesh patterns 23a to
23i and the pair of connecting pads P electrically insulated to one
another are formed. The light-emitting panel 20 includes the pair
of connecting pads P at positions indicated by the 0 marks in FIG.
14.
Next, as illustrated in FIG. 15, a thermoplastic resin 240 is
disposed on the surface of the light transmissive film 21 on which
the mesh patterns 23a to 23i are formed. The light-emitting
elements 30.sub.1 to 30.sub.8 are disposed on the thermoplastic
resin 240. At this time, the light-emitting elements 30.sub.1 to
30.sub.8 are positioned such that the connecting pads P formed at
the mesh patterns 23a to 23i are positioned immediately below the
bumps 37 and 38 of the light-emitting elements 30.sub.1 to
30.sub.8.
Next, as illustrated in FIG. 16, the light transmissive film 22
where the thermoplastic resin 240 is disposed at the lower surface
is disposed on the top surface side of the light transmissive film
21. The light transmissive films 21 and 22 are heated and
pressurized under vacuum atmosphere for press bonding. Accordingly,
first, the bumps 37 and 38 formed on the light-emitting element 30
penetrate the thermoplastic resin 240, reach the mesh patterns 23a
to 23i, and are electrically connected to these mesh patterns 23a
to 23i. Then, the thermoplastic resin 240 is gaplessly filled
between the conductor layer 23, the light transmissive films 21 and
22, and the light-emitting element 30. As illustrated in FIG. 3,
the thermoplastic resin 240 becomes the resin layer 24 that holds
the light-emitting element 30 between the light transmissive films
21 and 22. Through the above-described processes, the
light-emitting panel 20 is completed.
As illustrated in FIG. 9, the flexible cable 40 to which the
reinforcing plate 60 is pasted is connected to the light-emitting
panel 20 configured as described above. Implementing the connector
50 to this flexible cable 40 completes the light-emitting module 10
illustrated in FIG. 1.
With the light-emitting module 10 configured as described above,
when a DC voltage is applied to the conductor patterns 43a and 43b
illustrated in FIG. 4 via the connector 50, the light-emitting
element 30 constituting the light-emitting panel 20 emits the
light. Since the rated voltage of the light-emitting element 30 is
approximately 2.5 V, a voltage around 20 V is applied to the
conductor patterns 43a and 43b of the light-emitting module 10.
As described above, as illustrated in FIG. 7, with the
light-emitting module 10 according to the embodiment, the end
portions of the line patterns LX and LY constituting the one mesh
pattern and the end portions of the line patterns LX and LY
constituting the other mesh pattern project at the boundary between
one set of the adjacent mesh patterns. The line patterns of the one
mesh pattern and the line patterns of the other mesh pattern are
disposed in alternation along the boundary. Thus, a gap (a slit)
between the mesh patterns 23a to 23i is not a straight line but
becomes a zigzag shape, in other words, a wave shape. This
disperses parts where the light transmittance is high; therefore,
the boundary of the mesh patterns constituting the light-emitting
module 10 becomes unnoticeable.
For example, in the case where only the line patterns of the one
mesh pattern project at the boundary of the mesh patterns or the
line patterns of both of the adjacent mesh patterns do not project
at the boundary, the regions with high transmittance concentrate
along the boundary of the mesh patterns. In this case, the boundary
of the mesh patterns stands out. Meanwhile, this embodiment
disposes the end portions of the line patterns extending from the
different mesh patterns in alternation along the boundary.
Accordingly, the boundary of the mesh patterns becomes
unnoticeable.
With this embodiment, the light-emitting element 30 is connected
with the mesh patterns 23a to 23i. These mesh patterns 23a to 23i
are constituted of a metal thin film with the line width of about
10 .mu.m. This ensures sufficiently securing the light transmissive
property and the flexibility of the light-emitting panel 20.
With this embodiment, the conductor layer 23 constituted of the
mesh patterns 23a to 23i is formed on the top surface of the light
transmissive film 21 among one set of the light transmissive films
21 and 22. In view of this, the light-emitting panel 20 according
to the embodiment becomes thinner than a light-emitting panel where
conductor layers are formed on both the top surface and the lower
surface of the light-emitting element 30. This ensures improving
the flexibility and a degree of light transmissive property of the
light-emitting panel 20.
This embodiment describes the case where the end portions of the
line patterns LX and LY constituting the one mesh pattern and the
end portions of the line patterns LX and LY constituting the other
mesh pattern are disposed in alternation at the boundary of one set
of the adjacent mesh patterns. The configuration is not limited to
this. For example, the end portions of the line patterns LX and LY
constituting the one mesh pattern and the end portions of the line
patterns LX and LY constituting the other mesh pattern may be
alternately disposed at every plural pieces along the boundary.
For example, the end portions of the line patterns LX and LY
constituting the one mesh pattern and the end portions of the line
patterns LX and LY constituting the other mesh pattern may be
alternately arranged at every two pieces at the boundary between
one set of the adjacent mesh patterns.
For example, as illustrated in FIG. 13, this embodiment describes
the case where the end portions of the one mesh pattern 23a and the
end portions of the other mesh pattern 23b projecting at the
boundary between the adjacent mesh patterns are parallel. The
configuration is not limited to this. As illustrated in FIG. 17,
the end portions of the one mesh pattern 23a does not have to be
parallel to the end portions of the other mesh pattern 23b.
While the embodiment uses the thermoplastic resin as the resin
layer 24, a thermosetting resin may be used. Additionally, while
the embodiment forms the mesh-like conductor layer 23 and then cuts
the conductor layer 23 using the laser to form the mesh patterns
23a to 23i, the configuration is not limited to this. A solid
conductor layer is formed on the entire surface and then a mesh
process of the conductor layer and a cutting-out process of the
mesh patterns 23a to 23i may be simultaneously performed by
one-time photoetching. The mesh patterns 23a to 23i may be formed
by one-time printing process.
The mesh patterns 23a and 23i may be extracted with the mesh
patterns and the conductor patterns stacked and brought into
contact at the peripheral portion of the light-emitting panel.
Conductor layers (solid regions) on which the mesh process is not
performed may be left at the ends of the mesh patterns 23a and 23i,
and the conductor patterns may be stacked on and brought into
contact with the conductor layers.
While the embodiment connects the eight pieces of LEDs in series
and the power lines and the series-connecting wiring parts are
configured as the mesh patterns, a two-dimensional array where the
series-connected LEDs are additionally connected in series may be
configured.
While the first embodiment describes the case where a line width d1
of the thin film conductors constituting the mesh pattern is 10
.mu.m and an arrangement pitch d2 of the thin film conductors is
about 300 .mu.m, the values of the line width d1 and the
arrangement pitch d2 can be variously changed. However, it is
preferable that the line width d1 is in a range of 1 .mu.m or more
to 100 .mu.m or less, and the arrangement pitch d2 is in a range of
10 .mu.m or more to 1000 .mu.m or less.
FIG. 18A illustrates a correspondence table expressing
transmittances Pe1 of the mesh pattern (the conductor layer) itself
corresponding to the line widths d1 of the mesh pattern and the
arrangement pitches d2 of the mesh pattern. The unit of the line
widths d1 and the arrangement pitches d2 is micron (.mu.m). With
reference to FIG. 18A, to secure the light transmissive property of
the light-emitting module 10, it is considered to set the line
width d1 and the arrangement pitch d2 such that, for example, the
transmittance Pe becomes 75% or more. It is also considered to set
the line width d1 and the arrangement pitch d2 such that a sheet
resistance of the mesh pattern becomes 100.OMEGA.
(100.OMEGA./.quadrature.) or less.
For example, with the line width d1 of the mesh pattern of 1 .mu.m,
the arrangement pitch d2 of the mesh pattern where the
transmittance Pe1 of the mesh pattern becomes 75% or more and the
sheet resistance of the mesh pattern becomes 100.OMEGA. or less is
10 .mu.m. With the line width d1 of the mesh pattern of 5 .mu.m,
the arrangement pitch d2 of the mesh pattern where the
transmittance Pe1 becomes 75% or more and the sheet resistance of
the mesh pattern becomes 100.OMEGA. or less is 50 to 300 .mu.m.
Similarly, the arrangement pitch d2 where the transmittance Pe1 of
the mesh pattern becomes 75% or more and the sheet resistance of
the mesh pattern becomes 100.OMEGA. or less is 100 to 500 .mu.m
with d1 of 10 .mu.m, 200 to 500 .mu.m with d1 of 20 .mu.m, 300 to
500 .mu.m with d1 of 30 .mu.m, 500 to 1000 .mu.m with d1 of 50
.mu.m, and 1000 .mu.m with d1 of 100 .mu.m.
This secures the light transmissive property of the light-emitting
module 10 and also ensures decreasing the resistance of the mesh
pattern. It is only necessary to select the line width and the
arrangement pitch of the mesh pattern from the above-described d1
and d2 ranges. The above-described example specifies the upper
limit of d2 by the sheet resistance and a similar specification of
the argentum (Ag) mesh.
The transmittance may be set configuring the mesh pattern (the
conductor layer) and the light transmissive film as one unit. The
transmittance of a PET film with the thickness of 100 .mu.m is
approximately 91%. In this case, a transmittance Pe2 of the unit
constituted of the conductor layer 23 and the light transmissive
film 21 is preferably a value obtained by multiplying the
transmittance Pe1 in the correspondence table illustrated in FIG.
18A by 091 (=91%).
For example, the transmittances Pe2 in the correspondence tables
illustrated in FIG. 18B and FIG. 18C become the values found by
multiplying the transmittance Pe1 by 0.91 (=91%). In the case where
the conductor layer 23 is formed on the light transmissive film 21,
the line width d1 and the arrangement pitch d2 of the mesh pattern
need to be set such that the transmittances Pe2 illustrated in FIG.
18B (the Ag mesh) and FIG. 18C (the Cu mesh) become 75% or
more.
For example, with the conductor layer 23 being made of the argentum
(Ag), to set the transmittance Pe2 of 75% or more and the sheet
resistance of the mesh pattern of 100.OMEGA.
(100.OMEGA./.quadrature.) or less, the line width d1 and the
arrangement pitch d2 need to be set corresponding to the matrix
colored in the correspondence table illustrated in FIG. 18B. This
secures the light transmissive property of the light-emitting
module 10 and also ensures decreasing the resistance of the mesh
pattern. Here, the sheet resistance 100.OMEGA. corresponds to
almost 90% of the transmittance Pe2.
With the conductor layer 23 made of the argentum, the sheet
resistance becomes around 50.OMEGA./.quadrature. or less when the
line width d1 of 10 .mu.m and the arrangement pitch d2 of 500
.mu.m, or the line width d1 of 5 .mu.m and the arrangement pitch d2
of 300 .mu.m.
With the conductor layer 23 made of the copper (Cu), to set the
sheet resistance of the mesh pattern to 100.OMEGA.
(100.OMEGA./.quadrature.) or less, the line width d1 and the
arrangement pitch d2 need to be set corresponding to the matrix
colored in the correspondence table illustrated in FIG. 18C. This
secures the light transmissive property of the light-emitting
module 10 and also ensures decreasing the sheet resistance of the
mesh pattern. While in the range surrounded by a frame f1 in FIG.
18C, the sheet resistance of the mesh pattern becomes 100.OMEGA.
(100.OMEGA./.quadrature.) or less, the line width d1 is too small
relative to the arrangement pitch d2. In view of this, d1 and d2
corresponding to this range may be removed from the setting values
of the line width and the arrangement pitch.
With the conductor layer 23 made of the copper, the sheet
resistance becomes around 10.OMEGA./.quadrature. or less when the
line width d1 of 5 .mu.m and the arrangement pitch d2 of 300 .mu.m,
or the line width d1 of 10 .mu.m and the arrangement pitch d2 of
500 .mu.m.
As described above, the transmittance of the mesh pattern is
preferably 75% or more. Considering the mesh pattern and the light
transmissive film 21 as a unit, the transmittance may be configured
to be 75% or more. Alternatively, considering the mesh pattern, the
light transmissive film 21, and the resin layer 24 as a unit, the
total transmittance may be configured to be 60% or more, 70% or
more, or 75% or more. Further, considering the mesh pattern, the
light transmissive films 21 and 22, and the resin layer 24 as a
unit, the total transmittance may be configured to be 60% or more,
70% or more, or 75% or more.
The sheet resistance of the mesh pattern is preferably 100.OMEGA.
(100.OMEGA./.quadrature.) or less. With the mesh pattern made of
the argentum (Ag), obtaining the sheet resistance below 50.OMEGA.
is also possible. Accordingly, the mesh pattern with the sheet
resistance of 70.OMEGA./.quadrature. or less, for example,
50.OMEGA./.quadrature. or less can be easily achieved using the
argentum, an argentum alloy, or a similar material. By the use of
the copper (Cu), obtaining the sheet resistance less below
10.OMEGA. is also possible. Accordingly, the mesh pattern with the
sheet resistance of 30.OMEGA./.quadrature. or less, for example,
10.OMEGA./.quadrature. or less can be achieved using the copper, a
copper alloy, or a similar material.
As the mesh pattern, in addition to the argentum (Ag) and the
copper (Cu), an alloy and a compound of these materials may be
used. For example, with the argentum, Ag--Cu, Ag--Cu--Sn, and a
silver chloride (Ag--Cl), and with the copper, Cu--Cr and a similar
material are applicable.
Regarding the line width d1 of the mesh pattern and the arrangement
pitch d2 of the mesh pattern, the larger line width d1 and
arrangement pitch d2 make the line of the mesh pattern stand out.
In view of this, the line width d1 is preferably set to 50 .mu.m or
less and d2 to 1000 .mu.m or less. Preferably, the line width d1 is
20 .mu.m or less and the arrangement pitch d2 is 500 .mu.m or less,
and more preferably the line width d1 is 15 .mu.m or less and the
arrangement pitch d2 of 300 .mu.m or less. As one example, the line
width d1 is 20 .mu.m or less and the arrangement pitch d2 is 500
.mu.m or less.
The film thickness of the mesh pattern is configured to be 1 to 2
.mu.m. The one shown in FIG. 18C where the line width d1 of 1 .mu.m
and the arrangement pitch d2 of 200 to 1000 .mu.m has an elongate
shape, closing to an isolation pattern. Therefore, the use of the
one with the smaller arrangement pitch d2 is preferable so as not
to fall over the line pattern. The preferable ratio of the line
width/arrangement pitch (d1/d2) in terms of reliability is 0.002 or
more.
Second Embodiment
The following describes the second embodiment of the present
disclosure with reference to the drawings. Like reference numerals
designate corresponding or identical elements throughout the first
embodiment and the second embodiment, and therefore such elements
will not be further elaborated here. A light-emitting module 10A
according to the embodiment differs from the light-emitting module
10 according to the first embodiment in that the light-emitting
elements 30 are connected in parallel.
FIG. 19 is a plan view of the light-emitting module 10A according
to the embodiment. As illustrated in FIG. 19, the light-emitting
module 10A is a module having the longitudinal direction in the
Y-axis direction. This light-emitting module 10A includes 15 pieces
of light-emitting elements 30.sub.1 to 30.sub.15 as a light
source.
As apparent with reference to FIG. 3, the light-emitting module 10A
includes one set of the light transmissive films 21 and 22, the
resin layer 24 formed between the light transmissive films 21 and
22, and the 15 pieces of the light-emitting elements 30.sub.1 to
30.sub.15 disposed inside the resin layer 24.
Among one set of the light transmissive films 21 and 22, the
conductor layer 23 with the thickness of around 0.05 .mu.m to 10
.mu.m is formed on the lower surface of the light transmissive film
21. As illustrated in FIG. 19, the conductor layer 23 is
constituted of a plurality of mesh patterns 201 to 220. The mesh
patterns 201 to 220 are each made of a metallic material such as
the copper (Cu) and the argentum (Ag).
The respective mesh patterns 201 to 220 are shaped in an L shape.
The mesh pattern 201 is disposed at a region on the left side (the
-X-side) of the light transmissive film 21 along the outer edge on
the -X-side of the light transmissive film 21. The mesh patterns
202 to 209 are disposed in order from this mesh pattern 201 to the
inside. The mesh pattern 220 is disposed at a region on the right
side (the +X-side) of the light transmissive film 21 along the
outer edge on the +X-side of the light transmissive film 21. The
mesh patterns 219 to 210 are disposed in order from this mesh
pattern 201 to the inside.
In the light-emitting module 10A, the mesh pattern 201 is opposed
to the mesh patterns 218 to 220 so as to interpose a center line CL
passing through the center of the light transmissive film 21 and
parallel to the Y-axis. Similarly, the mesh patterns 202 to 204 are
opposed to the mesh pattern 217, the mesh pattern 205 is opposed to
the mesh patterns 214 to 216, the mesh patterns 206 to 208 are
opposed to the mesh pattern 213, and the mesh pattern 209 is
opposed to the mesh patterns 210 to 212.
15 pieces of the light-emitting elements 30.sub.1 to 30.sub.15 are
disposed at regular intervals on the center line CL and are
disposed across one set of the mesh patterns mutually opposed via
the center line CL. In view of this, configuring the mesh pattern
201 as a common pattern, the light-emitting elements 30.sub.1 to
30.sub.3 and the mesh patterns 218 to 220 are mutually connected in
parallel. Hereinafter, similarly, configuring the mesh pattern 217
as the common pattern, the light-emitting elements 30.sub.4 to
30.sub.6 and the mesh patterns 202 to 204 are mutually connected in
parallel. Configuring the mesh pattern 205 as a common pattern, the
light-emitting element 30.sub.7 to 30.sub.9 and the mesh patterns
214 to 216 are mutually connected in parallel. Configuring the mesh
pattern 213 as a common pattern, the light-emitting elements
30.sub.10 to 30.sub.12 and the mesh patterns 206 to 208 are
mutually connected in parallel. Configuring the mesh pattern 209 as
a common pattern, the light-emitting elements 30.sub.13 to
30.sub.15 and the mesh patterns 210 to 212 are mutually connected
in parallel.
As described above, with the light-emitting module 10A according to
the embodiment, the respective light-emitting elements 30.sub.1 to
30.sub.15 are connected in parallel to the mesh patterns 201, 205,
209, 213, and 217 as the common patterns. Accordingly, based on the
common patterns, applying predetermined voltages to the respective
mesh patterns 202 to 204, 206 to 208, 210 to 212, 214 to 216, and
218 to 220 connected to the respective light-emitting elements
30.sub.1 to 30.sub.15 allows individually driving the respective
light-emitting elements 30.sub.1 to 30.sub.15.
While the embodiment does not mention an emitted light color of the
light-emitting element 30, for example, implementing a
light-emitting element 30R, which emits the light in red, a
light-emitting element 30G, which emits the light in blue, a
light-emitting element 30B, which emits the light in green, and a
similar light-emitting element allows the light-emitting module to
emit the lights in various colors.
While the embodiment describes the light-emitting module 10A
including 15 pieces of the light-emitting elements 30 disposed at
the regular intervals, the configuration is not limited to this. By
disposing the light-emitting elements 30R, 30G, and 30B close to
the extent that the colors of the lights from the respective
light-emitting elements 30R, 30G, and 30B are mixed, the
light-emitting module may emit the light in neutral tint.
FIG. 20 is a drawing illustrating a light-emitting module 10B using
the light-emitting elements 30R, 30G, and 30B disposed close to one
another as a light source. As illustrated in FIG. 20, the
light-emitting module 10B includes five sets of the light-emitting
elements 30R, 30G, and 30B. The light-emitting elements 30R, 30G,
and 30B of each set are disposed to have an L-shape. The two
light-emitting elements 30G and 30B are disposed so as to be
adjacent to the light-emitting element 30R. A distance d between
the light-emitting element 30R and the light-emitting element 30G
and a distance d between the light-emitting element 30R and the
light-emitting element 30B are around 0.15 to 1 mm.
In the light-emitting module 10B, the light-emitting elements 30R,
30G, and 30B each emit the lights in red, blue, and green are
disposed close to one another. The respective light-emitting
elements 30R, 30G, and 30B can individually emit the lights. In
view of this, individually driving the light-emitting elements 30R,
30G, and 30B allows the light-emitting module 10 to emit the lights
in red, blue, green, white, and neutral tint.
As illustrated in FIG. 19 and FIG. 20, while this embodiment
describes the case where the light-emitting module 10 includes the
L-shaped mesh patterns 201 to 220, the mesh patterns are not
limited to the shape but any given shape can be determined. For
example, as illustrated in FIG. 21, the conductor layer 23 may be
constituted of a mesh pattern 221 as a common pattern, which is
connected to all the light-emitting elements 30R, 30G, and 30B of
the light-emitting module 10, rectangular mesh patterns 222 to 224,
and mesh patterns 225 to 230, which bend at a plurality of
sites.
Third Embodiment
FIG. 22A to 22D are connecting examples of the connecting pad P to
the mesh patterns. The connecting examples are applicable to both
the first embodiment and the second embodiment.
FIG. 22A illustrates an example where the connecting pad P is
connected to the mesh patterns by one line pattern. FIG. 22B and
FIG. 22C are examples of a high-density RGB light-emitting module
and are examples where the connecting pads P are connected to two
line patterns. FIG. 22B is a drawing illustrating mesh pattern at a
peripheral area of the light-emitting module as one example. FIG.
22C is a drawing illustrating mesh pattern at the intermediate
portion of the light-emitting module as one example. FIG. 22D is
another connecting example of the connecting pads P to the mesh
pattern.
In FIG. 22B to FIG. 22D, additional line patterns LP to connect the
line patterns LX and LY to the connecting pads P is formed in
addition to the existing line patterns LX and LY.
It is preferable for the connecting of the connecting pads P to the
mesh patterns to include the line patterns LP such that the number
of line patterns directly connected to the connecting pads P
becomes two or more. Disposing the additional line patterns LP
ensures improving strength of the mesh pattern. Additionally,
reliability against a pattern loss due to a process failure caused
by dust or a similar matter is enhanced.
Connecting the plurality of line patterns to the connecting pads P
allows decreasing currents flowing through the respective line
patterns LX and LY. This allows preventing disconnection of the
line patterns LX and LY and a similar failure due to overcurrent.
Accordingly, if by any chance, even if any of the plurality of line
patterns LX and LY is disconnected, the electric power can be
continuously supplied to the light-emitting element 30 implemented
to the connecting pad P via a good line pattern. Thus, the
additional line pattern LP can be disposed as a reinforcing
pattern.
Fourth Embodiment
The light-emitting module including the plurality of light-emitting
elements possibly has a limit in extension of a power supply line
using a one-layer wiring layer. FIG. 23A to FIG. 24B are drawings
illustrating examples of a light-emitting module where a wiring of
the light-emitting module is multilayered.
To configure a light transmission type light-emitting module into
multilayer, it is considered to configure the mesh patterns to be a
multilayer, and the respective layers are used as lower-layer
wirings and upper-layer wirings.
FIG. 23A to FIG. 23C are drawings describing a light-emitting
module including the light transmissive film 21 (the PET film)
where mesh patterns 301 and 302 are formed on front and back
surfaces. The light-emitting elements can be implemented to the
front and back surfaces of the light transmissive film 21. FIG. 23A
is a plan view of the light transmissive film 21. FIG. 23B is a
cross-sectional view of the light transmissive film 21. FIG. 23C is
a drawing illustrating a light-emitting module formed through
lamination of the light transmissive films 21. In this
light-emitting module, the two light transmissive films 21 are
disposed between one set of light transmissive films 303. The light
transmissive films 21 are mutually laminated via an adhesive layer
305.
As illustrated in FIG. 23A, the mesh patterns 301 and 302 formed on
the light transmissive film 21 are indicated by respective solid
lines and dashed lines. The line patterns of the mesh patterns 301
and 302 are displaced by a 1/2 pitch from one another. Connecting
portions 306 are disposed at sites where the mesh patterns 301 and
302 overlap. The connecting portion 306 can be formed by, for
example, disposing a through-hole on the light transmissive film
21, filling this through-hole with a conductive paste, and
performing plating. The mesh patterns 301 and 302 are electrically
connected by the connecting portions 306.
Similar to the first to the third embodiments, the light-emitting
element such as the LED is connected to one of the mesh patterns
among the mesh patterns 301 and 302 on the light transmissive films
21. In the case where a space is formed between the light
transmissive films, this space is filled with a resin. Black
circles in FIG. 23A indicate sites where the connecting portions
306 or the mutual mesh patterns 301 and 302 can be connected. The
mesh patterns 301 and 302 on the upper side and the lower side are
each processed into a desired wiring shape. Light-emitting elements
such as the LEDs may be separately connected to the mesh patterns
301 and 302 on both the front and back surfaces of the light
transmissive film 21. That is, a first light-emitting element may
be connected to one of the front and the back of the mesh pattern
301, and a second light-emitting element may be connected to the
other front or back of the mesh pattern 302.
FIG. 24A is a cross-sectional view illustrating the light
transmissive film 21 (the PET film) where the mesh pattern 301 is
formed and the light transmissive film 22 (the PET film) where the
mesh pattern 302 is formed. The mesh patterns 301 and 302 are
formed at the respective opposed surfaces of the light transmissive
films 21 and 22.
As apparent with reference to FIG. 23A, the mesh patterns 301 and
302 are indicated by the respective solid lines and dashed lines.
The line patterns of the mesh patterns 301 and 302 are displaced by
a 1/2 pitch from one another. The connecting portions 306 are
disposed at sites where the mesh patterns 301 and 302 overlap to
connect the mesh patterns 301 and 302.
Similar to the first to the third embodiments, the light-emitting
elements are connected to the mesh patterns 301 and 302 on the
light transmissive films 21 and 22. A space between the light
transmissive films 21 and 22 is filled with the resin. The mesh
patterns 301 and 302 are connected using, for example, 0.OMEGA.
resistance or a dummy chip. After the mesh patterns 301 and 302 are
extracted from the space between the light transmissive films 21
and 22, the mesh patterns 301 and 302 may be connected to one
another. While the light-emitting elements such as the LEDs are
connected to one of the mesh patterns 301 and 302, the
light-emitting elements such as the LEDs may be separately
connected to both the mesh patterns 301 and 302 as desired. That
is, the first light-emitting element may be connected to the mesh
pattern 301 and the second light-emitting element may be connected
to the mesh pattern 302.
As the light-emitting element of this example, in addition to the
light-emitting element of one surface with two electrodes type,
which is described in the first to the third embodiments, a
light-emitting element of electrode-on both-surfaces type, which
has electrodes on both surfaces, is also applicable. In the case of
the use of the light-emitting element of the electrode-on
both-surfaces type, one electrode is connected to the mesh pattern
301 and the other electrode is connected to the mesh pattern
302.
It is also possible that one conductor layer of multilayer wiring
is constituted of a mesh pattern and the other is constituted of a
light transmissive conductive film such as an ITO. It is also
possible that the multilayer wiring part is disposed only at the
peripheral portion of the light-emitting module and a base wiring
pattern such as the mesh pattern to which the light-emitting
element is connected itself is configured to have a multilayer
wiring structure.
Fifth Embodiment
FIG. 25A to FIG. 25F are drawings illustrating examples of other
mesh patterns. FIG. 25A illustrates a mesh pattern MP1 where line
patterns are inclines by 45.degree.. FIG. 25B illustrates a mesh
pattern MP2 where line patterns are formed of curved lines. FIG.
25C illustrates a mesh pattern MP3 where line patterns form
circles. FIG. 25D, FIG. 25E, and FIG. 25F illustrate mesh patterns
MP4, MP5, and MP6 where line patterns have polygonal shapes.
The light-emitting modules according to the first to the fourth
embodiments can be used for applications such as a display, a
decoration, and an illumination. However, in the case where a grid
pattern such as a stripe and a mesh is present close to the mesh
pattern that the light-emitting module has, a moire possibly occurs
between both. Hereinafter, for convenience of explanation, the mesh
pattern, the grid pattern, and a similar pattern constituted of the
high transmittance part and the low transmittance part are referred
to as a grid pattern for convenience.
For example, in the case where the light-emitting modules of the
first to the fourth embodiments are used as a backlight for a
liquid crystal display device in close contact with a liquid
crystal display, a displacement of pitches with a pixel array of
the opposite side possibly results in the moire. The mesh pattern
MP1 illustrated in FIG. 25A inclines the line patterns on the
light-emitting module side by 45.degree. with respect to the grid
pattern of the target such as the stripe and the mesh. The mesh
pattern MP1 is, for example, formed in a state inclined with
respect to a side of a square or rectangular light-emitting panel
by 45 degrees. Thus, inclining the line patterns of the mesh
pattern MP1 with respect to the target such as the liquid crystal
display ensures preventing the moire.
With the mesh pattern MP2 illustrated in FIG. 25B where the line
patterns are formed into the curved lines and the mesh pattern MP3
illustrated in FIG. 25C where the line patterns form the circles,
the line patterns and the grid pattern of the target do not
linearly intersect with one another, thereby bringing an effect of
preventing the moire. Additionally, the mesh patterns MP4, MP5, and
MP6 illustrated in FIG. 25D, FIG. 25E, and FIG. 26F where the
respective line patterns have the polygonal shapes (excluding the
square shapes) generate a diagonal component in the line patterns,
thereby also bringing the effect of preventing the moire.
While the examples of the mesh pattern where the light-emitting
module is applied as the backlight for the liquid crystal display
device are described above, in the case where the two mesh patterns
on the upper and the lower sides are present in the light-emitting
module like the fourth embodiment, the mesh patterns according to
FIG. 25A to FIG. 25F are applicable.
In the case where the mesh pattern illustrated in FIG. 25A is used,
it is only necessary that the line patterns of the one mesh pattern
among the two mesh patterns on the upper and the lower sides are
inclined with respect to the line patterns of the other mesh
pattern by 45.degree.. In the case where the mesh patterns
illustrated in FIG. 25B to FIG. 25F are used, it is only necessary
to combine the mesh patterns as necessary for application. For
example, the one mesh pattern is configured as a pattern formed of
a regular tetragon and the other mesh pattern is configured to be
any one of the mesh patterns illustrated in FIG. 25B to FIG. 25F.
It is also possible to combine the mesh patterns illustrated in
FIG. 25B to FIG. 25F.
Sixth Embodiment
While the embodiments of the present disclosure are described
above, the present disclosure is not limited to the embodiments.
For example, while the embodiment describes the case where the
light-emitting element 30 is disposed on the center line CL, the
configuration is not limited to this. For example, as illustrated
in FIG. 26, the light-emitting elements 30 may be disposed on a
curved line L1. FIG. 26 is a drawing developing a part of a cone in
a planar surface. This light-emitting module has a curved surface
in a finished state (an assembled state), and light-emitting
elements are arranged in a straight line at the peripheral area of
the cone.
In this case, it is considered that mesh patterns 231 to 238
constituting the conductor layer 23 are formed into a fan shape
having a pair of outer edges perpendicular to the curved line L1.
Forming the mesh patterns 231 to 238 into the fan shape allows the
sizes and the shapes of the respective mesh patterns 231 to 238 to
be uniform. This makes current densities of the respective mesh
patterns 231 to 238 constant, ensuring reducing heat generation and
a frequency of disconnection of the line patterns LX and LY.
The shape of the mesh patterns 231 to 238 constituting the
conductor layer 23 is not the fan shape but may be, for example, a
strip shape as illustrated in FIG. 27 having outer edges parallel
to one another. In this case, the shapes and the sizes of the mesh
patterns 231 to 238 possibly differ from one another depending on
the shape of the conductor layer 23. However, since the outer edges
of the mesh patterns 231 to 238 are parallel to one another, these
light-emitting elements 30 can be connected to the mesh patterns
231 to 238 without changing the degree of the light-emitting
element 30. Accordingly, to implement the light-emitting elements
30 using, for example, a mounter, the positioning of the
light-emitting elements 30 to the mesh patterns 231 to 238 is
facilitated.
In FIG. 26 and FIG. 27, the conductor layer 23 is constituted of
the mesh patterns. However, the configuration is not limited to the
mesh pattern, and a configuration where the conductor layer 23 is
constituted of the light transmissive conductive films such as the
ITOs is also applicable. A slit between the mesh patterns and the
ITO patterns may be a straight line shape or may be the zigzag
shape exemplified in the first embodiment.
Seventh Embodiment
While the embodiments use the one surface with two electrodes type
as the light-emitting element, as one example, a light-emitting
element 1 of the electrode-on both-surfaces type illustrated in
FIG. 28 is also usable as necessary. The light-emitting element 1
is a square LED chip with one side of 0.3 mm to 3 mm. As
illustrated in FIG. 28, the light-emitting element 1 includes a
base material 7, a P-type semiconductor layer 4, which is laminated
on the top surface of the base material 7, a light-emitting layer
(a PN bonded interface or a light-emitting site with double
heteroconnecting structure or a multiple quantum well structure) 5,
and a N-type semiconductor layer 6. The positions of the P-type
semiconductor layer 4 and the N-type semiconductor layer 6 may be
inversed. A pad 2 is disposed on the top surface of the P-type
semiconductor layer 4 and a pad 3 is disposed on the lower surface
of the base material 7. A bump 8 is disposed on the pad 2.
FIG. 29 is a side view of a light-emitting panel 20A including the
light-emitting element 1. The light-emitting panel 20A includes
conductor layers 23.sub.1 and 23.sub.2 on both the light
transmissive films 21 and 22. For example, the bump 8 is connected
to the conductor layer 23.sub.1 via the connecting pad P and the
pad 3 is connected to the conductor layer 23.sub.2.
FIG. 30A illustrates a mesh pattern MP8 constituting the conductor
layer 23.sub.1 and a mesh pattern MP7 constituting the conductor
layer 23.sub.2. As illustrated in FIG. 30A, line patterns of the
mesh pattern MP7 and line patterns of the mesh pattern MP8 mutually
form an angle of 45 degrees. This reduces the moire between the
mesh pattern MP7 and the mesh pattern MP8.
Various kinds of combinations are considered as combinations of the
mesh pattern of the conductor layer 23.sub.1 and the mesh pattern
of the conductor layer 23.sub.2. For example, like a mesh pattern
MP9 illustrated in FIG. 30B, the mesh pattern constituting the
conductor layer 23.sub.1 may be configured as a mesh pattern whose
line patterns constitute the polygonal shapes. For example, like a
mesh pattern MP11 illustrated in FIG. 30C, a mesh pattern whose
line patterns constitute the polygonal shape is formed at the
conductor layer 23.sub.1, and like a mesh pattern MP10, a mesh
pattern whose line patterns form the curved lines may be formed at
the conductor layer 23.sub.2. In such case as well, the moire can
be reduced between the mesh patterns of the respective conductor
layers 23.sub.1 and 23.sub.2.
The first embodiment to the seventh embodiment are described in
detail above. As described using FIG. 11 and FIG. 12, the
embodiments mainly describe the case where the conductor layer 23
is cut using the laser to form the mesh patterns 23a to 23i.
However, the configuration is not limited to this. The mesh
patterns 23a to 23i may be formed by photolithography, inkjet
application, screen-printing, and gravure printing.
As described in FIG. 15 and FIG. 16, while the embodiments describe
the case where the resin layer 24 is made of the thermoplastic
resin 240, the configuration is not limited to this. The resin
layer 24 may be made of a resin with a thermosetting property or a
combination of these resins. A resin layer may be left or may be
removed between the back surface of the light-emitting element and
the light transmissive film.
While embodiments describe that the mesh pattern is made of the
copper or the argentum, the configuration is not limited to this.
The mesh pattern may be made of a metal such as a gold (Au) and a
platinum (Pt).
The embodiments form the connecting pad P mainly as a wide-width
portion of the mesh pattern. While the connecting pad P is
generally a wide width extending portion of the mesh pattern, one
where a wide-width portion is disposed at an intersection point of
a grid to form a connecting pad, one where a grid is embedded to
form a connecting pad, and one where a mesh is thickened at a
peripheral area of a LED chip for connecting to the LED on a grid
are also included in the concept. The embodiments also permit
connecting at a side and an intersection point of the usual grid.
The embodiments also permit a constitution of a connecting pad by a
metal layer at a different layer from a mesh pattern.
In the case where the pitch of the line patterns constituting the
mesh pattern according to the embodiments is not the equal pitch,
it is considered that the degree of light transmissive property of
the light-emitting panel varies. For example, as illustrated in
FIG. 31A and FIG. 31B, in the case where a distance between two
mesh patterns MP12 and MP13 adjacent to a mesh pattern MPC is
smaller than a pitch of line patterns constituting the respective
mesh patterns, the degree of light transmissive property is
deteriorated at a boundary between the mesh pattern MP12 and the
mesh pattern MP13. In such case, as illustrated in FIG. 31A and
FIG. 31B, partially thinning out the line patterns of the mesh
patterns MP12 and MP13 ensures reducing the variation of the degree
of light transmissive property of the light-emitting panel.
The mesh patterns illustrated in FIG. 31A and FIG. 31B are also
effective to make a gap between the mesh patterns unnoticeable.
FIG. 31C illustrates the case where one line pattern is removed
from a two-dimensional mesh pattern to produce the two mesh
patterns MP12 and MP13, which are electrically isolated to the
right and the left. FIG. 31D illustrates the case where the two
mesh patterns MP12 and MP13 having opposed sides are disposed close
to one another. The above-described structures illustrated in FIG.
31A and FIG. 31B are effective to make the gap between the mesh
patterns MP12 and MP13, which are close to one another as
illustrated in FIG. 31D, unnoticeable. The gap in the vertical
direction between the mesh patterns can be formed into the
above-described zigzag slits or formed by partially thinning out
the opposed line patterns or by combining these methods.
The first embodiment, the second embodiment, the third embodiment,
the fourth embodiment, the fifth embodiment, the sixth embodiment,
and the seventh embodiment of the present disclosure are described
above. Obviously, these first to seventh embodiments can be
mutually combined.
While some embodiments of the present disclosure have been
described, these embodiments have been presented by way of example
only, and are not intended to limit the scope of the invention.
Indeed, the novel embodiments described herein may be embodied in a
variety of other forms; furthermore, various omissions,
substitutions and changes in the form of the embodiments described
herein may be made without departing from the spirit of the
invention. The accompanying claims and their equivalents are
intended to cover such forms or modifications as would fall within
the scope and spirit of the inventions.
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